[X86] Introduce WriteFLDC for x87 constant loads.
Summary:
{FLDL2E, FLDL2T, FLDLG2, FLDLN2, FLDPI} were using WriteMicrocoded.
- I've measured the values for Broadwell, Haswell, SandyBridge, Skylake.
- For ZnVer1 and Atom, values were transferred form InstRWs.
- For SLM and BtVer2, I've guessed some values :(
Reviewers: RKSimon, craig.topper, andreadb
Subscribers: gbedwell, llvm-commits
Differential Revision: https://reviews.llvm.org/D47585
llvm-svn: 333656
diff --git a/llvm/lib/Target/X86/X86Schedule.td b/llvm/lib/Target/X86/X86Schedule.td
index ad31690..ccee972 100644
--- a/llvm/lib/Target/X86/X86Schedule.td
+++ b/llvm/lib/Target/X86/X86Schedule.td
@@ -143,6 +143,7 @@
// Floating point. This covers both scalar and vector operations.
def WriteFLD0 : SchedWrite;
def WriteFLD1 : SchedWrite;
+def WriteFLDC : SchedWrite;
def WriteFLoad : SchedWrite;
def WriteFLoadX : SchedWrite;
def WriteFLoadY : SchedWrite;